Fire hydrant drainage valve

ABSTRACT

A fire hydrant having a valve seat and a valve stem having a valve thereon seating on the valve seat, drain passages through the valve seat leading externally of the hydrant and spring loaded means on the valve stem closing the drain passages rapidly during the initial opening movement of the hydrant valve.

United States Patent 1191 Daigle Jan. 15, 1974 [54] HYDRANT DRAINAGE VALVE FOREIGN PATENTS OR APPLICATIONS Inventor: Rosflil'e Daigle, Lambert, 1,097,353 1/1968 Great Britain 137/5l6.15

Quebec, Canada [73] Assignee: Daigle Aqua Inc., Quebec, Canada P i Examiner--Robert G. Nilson [22] Filed: Aug. 20 1971 AttorneyLarson, Taylor and Hinds [2]] Appl. No.: 173,544

57 ABSTRACT [52] US. Cl. 137/305 A fir hyd ant having a valve seat and a valve stem [51 Int. Cl. Fl6k 1/00 havi g a alve thereon seating on the valve seat, drain Field of Search 529, passages through the valve seat leading externally of 3 627-5 the hydrant and spring loaded means on the valve stem closing the drain passages rapidly during the inil References Cled tial opening movement of the hydrant valve.

UNITED sTATEs PATENTS 1.083.307 1/1914 Thornc 137/305 x 5 2 Drawmg Flgures 0 35 a4 40 3e 0 A PATENIED I 51974 3.785.399

sum 1 or 2 [N VE N TOR Rosuire DAIGLE 4M, Iz ir JAN 1 515174 SHEET 2 BF 2 IX'VEX Rosuire DAI FIRE HYDRANT DRAINAGE VALVE This invention relates to improvements in fire hydrants and to a new or improved drain valve means for a hydrant.

Known hydrant drain valves employ a gate moving vertically with the valve stem to open and close the drain passages on the sides of the main valve seat casting. Such drain valves usually require at least seven turns on opening of the main valve stem before the drain valve is closed. In some operations, for example where the hydrant is used for street flushing, the operator only opens the main valve an amount sufficient to obtain the flow of water required, with the result that the drain valve remains open and there is a constant leakage of water into the surrounding soil. According to the present invention there is provided a fire hydrant comprising a casing within which is mounted an annular valve seat and a hydrant valve closure member carried upon a stem and movable axially therewith to cooperate with the valve seat, drain valve means comprising a plurality of drain passages opening from the downstream side of said valveseat and leading from the interior to the exterior of said casing, and drain valve closure means comprising a yoke having a central boss through which said stem is axially movable and a plurality of limbs extending generally radially therefrom, each limb supporting at its radially outermost end a closure element which co-operates with a respective one of said drain passages, said yoke being resiliently urged by individual spring means associated with each of said limbs in a direction such as to close said drain passages, abutment means on said stem being positioned to engage said yoke when the hydrant valve closure is seated and maintain said closure elements out of engagement with said drain passages, said drain passages being rapidly sealed by said closure elements under the force of said spring means during the initial opening movement of said hydrant valve. By virtue of the individual spring means the drain valve passages are closed on only two turns of the main valve stem in the opening direction.

The drain passages may be formed inthe annular valve seat itself and are preferably three in number being arranged at equal angular intervals about the axis of the valve, the yoke having a corresponding number of radially extending .limbs. Preferably second abutment means are provided on said stem, axially spaced from the first mentioned abutment means and are effective to engage the yoke as the hydrant valve closure approaches its fully open position and press the closure elements on the limbs of the yoke firmly into engagement with the drain passages, a supporting shoulder associated with each said closure element being adapted to engage a rigid relatively stationary part of the hydrant to support said closure element against excessive compression.

A preferred embodiment of the fire hydrant according to this invention will now be described with reference to the accompanying drawings in which:

FlG. 1 is a longitudinal sectional view of a fire hydrant valve, the valve being shown closed in the right hand half of the drawing and fully opened in the left hand half;

FIG. 2 is a fragmentary end elevation of the hydrant partly sectioned to show details of drain valve means. In the drawings only the lower end of the hydrant is illustrated and this comprises a casing in the form of a cylindrical barrel having at its lower end an annular flange l1 bolted to a mating flange 12 on a base casting 13. The base casting 13 is in the form of an elbow connector and has at its other end a further flange 14 for connection to a water main (not illustrated).

The upper end of the base casting 13 is formed with a threaded bore 15 in which is received an annular valve seat 16 which is sealed to the base casting by means of O-ring seals 17 and 18 at its upper and lower ends respectively. The lower end of the valve seat 16 is formed with a frustoconical seating surface 19.

Within the hydrant a valve closure member indicated at 20 is mounted to eo-operate with the valve seat 16 in forming the hydrant valve. The valve closure is carried on a square sectioned stem 21 which extends axially upwards within the barrel 10 and is supported in non-rotatable relationship thereto. The valve closure 20 comprises a valve flange 22, a valve element 23 and a valve nut 24 through which the lower end of the stem 21 passes. The lower end of the stem is screw threaded as at 25 and engaged by a castle nut 26 which clamps the valve closure 20 against the shoulder 27 on the valve stem and is retained by a cotter pin 28 passed through a bore in the screw threaded portion of the valve stem.

The valve element 23 is formed with a frustoconical surface 29 which mates with the surface 19 of the valve seat 16 and is adapted to co-operate therewith in sealing the hydrant valve. The upper end of the hydrant (not shown) is provided with conventional actuating means to effect opening and closing of the hydrant valve through axial movement of the stem 21.

The hydrant is provided with drain valve means in the form of three axially directed passages 30 formed in the valve seat 16 and arranged at equal angular intervals thereon. The upper end of each of these passages 30 is defined by a hollow fitting 31 in threaded engagement with the valve seat 16 and the lower end of each of the passages 30 communicates with an annular collection chamber 32 defined by registering grooves in the valve seat 16 and base casting 13. Openings 33 provide communication from the chamber 32 to the exterior of the hydrant casing.

Supported in the valve seat 16 is a yoke 34 comprising a central square section boss 35 and three limbs 36 extending generally radially therefrom at equal angular intervals about the axis of the valve stem. Each limb 36 comprises a detent 37 which is received in an axially extending groove 38 formed on the inner periphery of the valve seat 16. The valve stem 21 is movable axially within the boss 35 of the yoke. Each limb 36 of the yoke also carries at its radial outermost end a closure element 39 of resilient impermeable material positioned to co-operate with a corresponding one of the hollow fittings 31 to seal the drain passages 30. The closure elements 39 are maintained against angular displacement by the engagement of the detents 37 of the yoke in the grooves 38 of the valve seat and are further located by means of headed set pins 40. Adjacent each of the drain passages 30 in the valve seat is mounted one of the pins 40 extending upwards in an axial direction from the valve seat and having a plane cylindrical shank which passes with clearance through an aperture in the end of the corresponding limb 36 of the yoke. As illustrated the shank of each pin 40 is surrounded by a coiled compression spring 41 arranged with its respective ends pressing against the underside of the head of the pin and the outermost end of the limb 36 of the yoke. It will thus be apparent that the springs 41 act to urge the closure element 39 into sealing engagement with the hollow fittings 31 which define the openings of the drain passages 30.

As illustrated in the right hand part of FIG. 1 when the hydrant valve closure 20 is seated against the valve seat 16 the upper end of the valve flange is engaged against the boss 35 of the yoke and is effective to hold the closure element 39 out of sealing engagement with the hollow fittings 31. Thus when the hydrant valve is closed the drain valve means defined by the passages 30, collection chamber 32 and openings 33 is opened, allowing any water contained in the barrel to drain out of the hydrant. Upon opening of the hydrant valve the stem 21 moves downwards disengaging the valve flange 22 from the boss 35 of the yoke, and the yoke is then free to move downwards under the influence of the compression springs 41 to bring the closure elements 39 into sealing engagement with the hollow fittings 31 thus sealing the drain valve means. The arrangement is such that sealing of the drain valve means is effected rapidly during the initial opening movement of the hydrant valve so that the possibility of leakage from the hydrant at small openings of the hydrant valve is substantially eliminated.

As the hydrant valve approaches its fully opened position illustrated in the left hand side of FIG. 1 a plate 42 fixed to the valve stem engages the upper end of the boss 35 of the yoke and applies an additional force to the yoke to maintain the closure element 39 in sealing engagement with the fittings 31 of the drain passages. To prevent damage to the closure element 39 as a result of excessively high pressure being applied to the yoke by the plate 42 the outermost end of each limb 36 of the yoke is formed with a supporting shoulder 43 which is adapted to abut the upper surface of the valve seat 16 and thus relieve the corresponding closure element 39 from undue compression.

What is claimed as new is:

1. In a fire hydrant comprising a casing within which is mounted an annular valve seat and a hydrant valve closure member carried upon a stem and movable axially therewith to co-operate with the valve seat, drain valve means comprising a plurality of drain passages opening from the downstream side of said valve seat and leading from the interior to the exterior of said casing, and drain valve closure means comprising a yoke having a central boss through which said stem is axially movable and a plurality of limbs extending generally radially therefrom, each limb supporting at its radially outermost end a closure element which co-operates with a respective one of said drain passages, said yoke being resiliently urged by individual spring means associated with each of said limbs in a direction such as to close said drain passages, the said individual spring means including a headed pin in threaded engagement with a relatively stationary part of the hydrant and having a shank which passes with clearance through a bore in the outermost end of the corresponding yoke limb, said individual spring means comprising a coiled compression spring surrounding the shank of said pin with its respective ends pressing against said yoke limb and the head of said pin, first abutment means on said stem being positioned to engage said yoke when the hydrant valve closure is seated and maintain said closure elements out of engagement with said drain passages, said drain passages being rapidly sealed by said closure elements under the force of said spring means during the initial opening movement of said hydrant valve, and second abutment means axially spaced on said stem from said first abutment means for engaging said yoke as the hydrant valve closure approaches its fully open position for pressing said closure elements on the limbs into sealing engagement with their respective drain passages.

2. A fire hydrant according to claim 1 wherein each limb of the yoke has associated therewith a detent which is received in an axially extending groove formed on the inner periphery of said hydrant valve seat, the yoke and each said detent being axially but not rotatably movable with respect to said seat.

3. A fire hydrant according to claim 1 wherein said first abutment means on said stem comprises a part of the hydrant valve closure member.

4. A fire hydrant according to claim 3 wherein each said closure element has associated therewith a supporting shoulder engageable with a rigid relatively stationary part of the hydrant to support said closure element against excessive compression resultant upon engagement of said second abutment means with said yoke.

5. In a fire hydrant comprising a casing within which is mounted an annular valve seat and a hydrant valve closure member carried upon a stem and movable axially therewith to co-operate with the valve seat, drain valve means comprising a plurality of drain passages opening from the downstream side of said valve seat and leading from the interior to the exterior of said cas ing, and drain valve closure means comprising a yoke having a central boss through which said stem is axially movable and a plurality of limbs extending generally radially therefrom, each limb supporting at its radially outermost end a closure element which co-operates with a respective one of said drain passages, said yoke being resiliently urged by individual spring means associated with each of said limbs in a direction such as to close said drain passages, the said individual spring means including a headed pin in threaded engagement with a relatively stationary part of the hydrant and having a shank which passes with clearance through a bore in the outermost end of the corresponding yoke limb, said individual spring means comprising a coiled compression spring surrounding the shank of said pin with its respective ends pressing against said yoke limb and the head of said pin, abutment means on said stem being positioned to engage said yoke when the hydrant valve closure is seated and maintain said closure elements out of engagement with said drain passages, said drain passages being rapidly sealed by said closure elements under the force of said spring means during the initial opening movement of said hydrant valve, and wherein each limb of the yoke has associated therewith a detent which is received in an axially extending groove formed on the inner periphery of said hydrant valve seat, the yoke and each said detent being axially but not rotatably movable with respect to said seat. 

1. In a fire hydrant comprising a casing within which is mounted an annular valve seat and a hydrant valve closure member carried upon a stem and movable axially therewith to co-operate with the valve seat, drain valve means comprising a plurality of drain passages opening from the downstream side of said valve seat and leading from the interior to the exterior of said casing, and drain valve closure means comprising a yoke having a central boss through which said stem is axially movable and a plurality of limbs extending generally radially therefrom, each limb supporting at its radially outermost end a closure element which co-operates with a respective one of said drain passages, said yoke being resiliently urged by individual spring means associated with each of said limbs in a direction such as to close said drain passages, the said individual spring means including a headed pin in threaded engagement with a relatively stationary part of the hydrant and having a shank which passes with clearance through a bore in the outermost end of the corresponding yoke limb, said individual spring means comprising a coiled compression spring surrounding the shank of said pin with its respective ends pressing against said yoke limb and the head of said pin, first abutment means on said stem being positioned to engage said yoke when the hydrant valve closure is seated and maintain said closure elements out of engagement with said drain passages, said drain passages being rapidly sealed by said closure elements under the force of said spring means during the initial opening movement of said hydrant valve, and second abutment means axially spaced on said stem from said first abutment means for engaging said yoke as the hydrant valve closure approaches its fully open position for pressing said closure elements on the limbs into sealing engagement with their respective drain passages.
 2. A fire hydrant according to claim 1 wherein each limb of the yoke has associated therewith a detent which is received in an axially extending groove formed on the inner periphery of said hydrant valve seat, the yoke and each said detent being axially but not rotatably movable with respect to said seat.
 3. A fire hydrant according to claim 1 wherein said first abutment means on said stem comprises a part of the hYdrant valve closure member.
 4. A fire hydrant according to claim 3 wherein each said closure element has associated therewith a supporting shoulder engageable with a rigid relatively stationary part of the hydrant to support said closure element against excessive compression resultant upon engagement of said second abutment means with said yoke.
 5. In a fire hydrant comprising a casing within which is mounted an annular valve seat and a hydrant valve closure member carried upon a stem and movable axially therewith to co-operate with the valve seat, drain valve means comprising a plurality of drain passages opening from the downstream side of said valve seat and leading from the interior to the exterior of said casing, and drain valve closure means comprising a yoke having a central boss through which said stem is axially movable and a plurality of limbs extending generally radially therefrom, each limb supporting at its radially outermost end a closure element which co-operates with a respective one of said drain passages, said yoke being resiliently urged by individual spring means associated with each of said limbs in a direction such as to close said drain passages, the said individual spring means including a headed pin in threaded engagement with a relatively stationary part of the hydrant and having a shank which passes with clearance through a bore in the outermost end of the corresponding yoke limb, said individual spring means comprising a coiled compression spring surrounding the shank of said pin with its respective ends pressing against said yoke limb and the head of said pin, abutment means on said stem being positioned to engage said yoke when the hydrant valve closure is seated and maintain said closure elements out of engagement with said drain passages, said drain passages being rapidly sealed by said closure elements under the force of said spring means during the initial opening movement of said hydrant valve, and wherein each limb of the yoke has associated therewith a detent which is received in an axially extending groove formed on the inner periphery of said hydrant valve seat, the yoke and each said detent being axially but not rotatably movable with respect to said seat. 